Surface box 20mm knock out
Used these to mount thermostats with cable glands in the knock out holes.
I pushed the knockouts from the outside and they broke away cleanly. It requires a fair bit of force.
Good price and fine for what I needed.
11 Dec 2014

Inexpensive and simple
For those having issues reliably removing the cut-out, this approach works for me every time...
Drill a central hole about the same diameter of your screwdriver, insert screwdriver, and lever to one side. The cutout should then come straight out cleanly.
3 Dec 2014

Ideal trunking to conduit box
Great box for connecting 20mm plastic conduit to plastic trunking. Only gave 4* on performance because the knockout didn't work for the 20 mm hole and had to be drilled. I box was badly broken because of this so beware.
26 Dec 2012

Limited functionality
This surface box only has ONE circular knockout on one of its sides (there is another one on its back/base). This greatly limits its functionality, and to be honest it is the first time I have come across a surface box designed for conduit that only has ONE knockout for circular conduit entry on its side. This box can therefore only be used if your wiring is terminating at this box.
10 May 2012

We've noticed that you have cookies disabled. Screwfix.com requires cookies to be enabled in order to work properly - find out how to enable cookies. If you'd prefer not to enable cookies you will be able to view products but won't be able to purchase. Remember you can shop with us on the phone on 0500 414141 (mobile friendly 03330 112 112) or at over 280 stores.